I saw a filming run at Glen Waverley yesterday. It seemed to involve five or six schoolgirls, an older guy in a top hat, with a youngish boy who I guess would be his grandson in the film, and a lead lady in eye-assaulting pink. They had a six car Xtrap (878...936) of which they were using the front half only. Interestingly, one of the props was a cardboard version of a Metlink station sign, the name of which ended in "lanbelle" (I couldn't see the rest).
It hung around long enough for me to do as much snooping as I could without making it too obvious, but I couldn't find any reference to the name of the film, or the purpose or anything useful like that.